updated 11:35 pm EST, Tue November 12, 2013

FaceTime alone responsible for 1.4 percent of all upstream data

A new study from analysis and tracking firm Sandvine shows that some of Apple's web services - in particular, its iTunes stores - are among the most popular such services in North America, and growing rapidly. Since May, iTunes has grown more than 60 percent, from 1.9 percent of all downstream traffic to 3.27 percent. FaceTime, which is considered a wholly upstream service, was ahead of Dropbox and just behind Facebook in terms of upstream traffic.

The iTunes stores are responsible for 3.27 percent of all downstream web traffic in North America, just behind BitTorrent with four percent. The latter service -- mostly used for pirating media and software -- has dropped by more than 20 percent since May, when it occupied 5.57 percent of downstream traffic. In terms of upstream data, however, the service still dominates: it's responsible for a whopping 36.35 percent of upstream traffic from users.

Apple's iTunes popularity was good enough to rank it fifth among the downstream services, and also fifth among "aggregate" services (which includes upstream and downstream data) with 2.91 percent. In both the downstream and aggregate categories, Netflix was the dominant service with around 30 percent of such traffic in North America. This was followed by YouTube in second place with around 18 percent, general web surfing with just under 10 percent, then BitTorrent in fourth place.

Interestingly, iTunes' use indicated that it is about twice as commonly used as Amazon Video, which in turn appears to be about 50 percent more popular than Hulu (Facebook downstream traffic is rated between the two, but that comes mostly from embedded video viewing). It terms of upstream data from users to services, beyond BitTorrent in the top spot the next most popular service was generally HTTP web surfing, followed by SSL surfing, Netflix, YouTube, Skype, QVoD and then Facebook, just 0.1 percent higher than FaceTime. Dropbox rounded out the top 10 upstream services with 1.39 percent of North American traffic.

In aggregate, the top 10 services consume just over 73 percent of all NA web bandwidth. Netflix and YouTube combined take up about half of the bandwidth.